Recent advance in IT technology led to a development of a diversity of wireless communication technologies. Among them, wireless LAN allows users to have their portable devices, such as PDAs (Personal Digital Assistants), laptop computers, or portable multimedia players (PMPs), wirelessly access the Internet at home or workplace or in a certain service area.
In contrast to existing wireless LAN systems supporting HT (high throughput) and VHT (very high throughput), using transmission channels having a bandwidth of 20/40/80/160/80+80 MHz in a band of 2 GHz and/or 5 GHz, a wireless LAN system has been suggested of being able to operate in a band of 1 GHz or less. If a wireless LAN system operates in a band of 1 GHz or less, the wireless LAN system adopts a channel having a considerably narrow bandwidth as compared with the existing wireless LAN system. Accordingly, further expanded service coverage may be achieved.
A next-generation wireless LAN system may provide a lower data transmission speed than that provided by the existing wireless LAN systems due to the characteristics of its physical layer. In such environment, there is a need for a scanning method that may support a station so that the station may be more efficiently associated with an access point.